Bi-directional cutting or trimming knife

Abstract

A cutting or trimming knife for cutting or trimming the edges of sheet members is bi-directional and capable of moving downwardly and in a first lateral direction, or alternatively downwardly and in a second opposite lateral direction. The knife is held by a guide mechanism capable of shifting between first and second positions to cause the bi-directional movement of the knife.

What is claimed is:  
     
       1. Apparatus for cutting or trimming a stack of sheet members comprising: 
       a cutting table;  
       an elongated knife having a cutting edge extending along an elongated cutting edge axis;  
       a knife supporting frame connected to said cutting table;  
       a guide mechanism mounting said knife to said supporting frame for movement of said knife from one of a plurality of start positions wherein said knife is positioned spaced from said cutting table and said stack of sheet members to a cut position wherein said knife is positioned proximate said cutting table, wherein said knife moves towards said cutting table and trims or cuts said stack of sheet members;  
       at least a portion of said guide mechanism being movable on said frame to a first guide position causing said knife to be positioned in a first start position and to move in a first direction relative to said cutting edge axis when moving from said first start position to said cut position;  
       at least a portion of said guide mechanism being movable on said frame to a second guide position causing said knife to be positioned in a second start position and to move in a second direction opposite from said first direction when moving from said second start position to said cut position;  
       said guide mechanism comprising a linkage mechanism, wherein said linkage mechanism includes an elongated base link, a first link pivotally connected to said base link and said knife, and a second link pivotally connected to said base link and said knife; and  
       a linkage power means connected to said linkage mechanism for moving said linkage mechanism between said between said first and second guide positions, said linkage power means being connected to said base link and said support frame.  
     
     
       2. Apparatus according to  claim 1  wherein said linkage power means comprises an extensible fluid cylinder. 
     
     
       3. Apparatus according to  claim 1  wherein said base link, said first and second links, and said knife combine to form a parallelogram. 
     
     
       4. Apparatus according to  claim 3  wherein said guide mechanism further comprises at least one guide track attached to said frame, said linkage mechanism having a track follower guided within said guide track for guided movement therein during movement of said linkage mechanism between said first and second guide positions. 
     
     
       5. Apparatus for trimming or cutting a stack of sheet members comprising: 
       a cutting table;  
       a support frame connected to said cutting table and extending upwardly therefrom;  
       a linkage mechanism comprising a base link and first and second side links pivotally connected to said base link and extending downwardly therefrom;  
       an elongated knife holder having an elongated knife with a cutting edge mounted thereto, and being pivotally connected to said first and second side links, whereby said base link, said first and second side links, and said knife holder form a collapsible parallelogram;  
       an extensible cylinder connected to said frame and to said knife holder for moving said knife from one of a plurality of start positions spaced from said table to a cut position proximate said table;  
       said base link being movably mounted to said support frame for movement from a first link position wherein said first and second links angle downwardly at an inclined first angle when said knife is in a first start position to a second link position wherein said first and second side links angle downwardly at an inclined second angle opposite from said first angle when said knife is in a second start position.  
     
     
       6. Apparatus for cutting or trimming a stack of sheet members comprising: 
       a cutting table;  
       an elongated knife having a substantially straight cutting edge extending along an elongated cutting edge axis;  
       a knife supporting frame connected to said cutting table;  
       a guide mechanism mounting said knife to said supporting frame for movement of said knife from one of a plurality of start positions wherein said knife is positioned spaced from said cutting table and said stack of sheet members to a cut position wherein said knife is positioned proximate said cutting table, wherein said knife moves toward said cutting table and trims or cuts said stack of sheet members;  
       at least a portion of said mechanism guide being movable on said frame to a first guide position of the guide mechanism for causing said knife to be positioned in a first start position and to move in a first direction relative to said cutting edge axis when moving from said first start position to said cut position; and  
       at least a portion of said guide mechanism being movable on said frame to a second guide position of the guide mechanism for causing said knife to be positioned in a second guide position and to move in a second direction opposite from said first direction when moving from said start position to said cut position.  
     
     
       7. Apparatus according to  claim 6  wherein said guide mechanism comprises a linkage mechanism. 
     
     
       8. Apparatus according to  claim 7  wherein said linkage mechanism includes an elongated base link, a first link pivotally connected to said base link and said knife, and a second link pivotally connected to said base link and said knife. 
     
     
       9. Apparatus according to  claim 8  and further comprising a linkage power means connected to said linkage mechanism for moving said linkage mechanism between said first and second guide positions. 
     
     
       10. Apparatus according to  claim 9  wherein said linkage power means comprises an extensible fluid cylinder. 
     
     
       11. Apparatus according to  claim 9  wherein said linkage power means is connected to said base link and said support frame. 
     
     
       12. Apparatus according to  claim 9  wherein said base link, said first and second links, and said knife combine to form a parallelogram. 
     
     
       13. Apparatus according to  claim 12  wherein said guide mechanism further comprises at least one guide track attached to said frame, said linkage mechanism further having a track follower guided within said guide track for guided movement therein during movement of said linkage mechanism between said first and second guide positions.